Moderna Makes History as FDA Approves the World’s First mRNA-Based Seasonal Flu Vaccine for Millions of Adults

The United States has approved Moderna’s first mRNA-based seasonal influenza vaccine, marking a historic milestone for the biotechnology company and the broader future of vaccine development. The approval makes the new shot, mFlusiva, the first flu vaccine to use messenger RNA (mRNA) technology—the same platform that helped produce COVID-19 vaccines in record time during the pandemic.

The decision by the U.S. Food and Drug Administration (FDA) is being viewed as a major breakthrough for Moderna, which has been working to expand its vaccine portfolio beyond COVID-19 as demand for coronavirus vaccines has declined in recent years. The company hopes the approval will strengthen confidence in mRNA technology and pave the way for future vaccines targeting multiple infectious diseases.

Unlike traditional flu vaccines, which are often produced using chicken eggs or cell-based manufacturing processes, mRNA vaccines work by delivering genetic instructions that prompt the body’s cells to produce harmless proteins resembling part of the influenza virus. This triggers the immune system to build protection without exposing a person to the actual virus. One of the biggest advantages of the technology is speed, allowing manufacturers to update vaccines more quickly when influenza strains change from season to season.

The FDA’s approval was supported by results from a large Phase 3 clinical trial involving more than 40,000 participants. According to Moderna, the vaccine reduced the risk of influenza by approximately 26.6% more than a standard licensed flu vaccine. In adults aged 65 and older, the vaccine also generated stronger immune responses than one of the leading high-dose flu vaccines currently available, although Moderna must complete additional post-approval studies to further confirm its effectiveness in that age group.

The vaccine has received traditional approval for adults aged 50 to 64, while approval for adults aged 65 and older has been granted through the FDA’s accelerated approval pathway. That means Moderna will continue collecting additional real-world data to verify long-term benefits for older adults, who remain among those most vulnerable to severe influenza complications.

For Moderna, the approval represents an important turning point. The company became globally recognised after developing one of the first successful COVID-19 vaccines, but falling pandemic-related demand has led it to invest heavily in new vaccines targeting influenza, respiratory viruses, cancer, and rare infectious diseases. The company is also developing combination vaccines that could eventually protect against both influenza and COVID-19 with a single injection.

Public health experts say influenza remains a significant global health challenge, causing millions of severe illnesses and hundreds of thousands of deaths worldwide each year. Because flu viruses mutate constantly, vaccines must be updated annually to match circulating strains. Researchers believe mRNA technology could make this process faster and more accurate, potentially improving vaccine effectiveness in future flu seasons.

Although Moderna does not expect mFlusiva to generate substantial revenue until after the current vaccination cycle, the approval is widely regarded as an important validation of mRNA technology beyond COVID-19.